High speed grounding switch



Nov. l0, 1964 K. H. DATE HIGH SPEED GROUNDING SWITCH 4 Sheets-Sheet l Filed March 9, 1961 INVENTOR. Kazaa FZ5/vif 5,47 BY jf/dal .TTbe/Vfy Nov. l0, 1964 K. H. DATE HIGH SPEED GROUNDING swxTcH 4 Sheets-Sheet 2 Filed March 9, 1961 Nov. 10, 1964 K. H. DATE 3,156,800

HIGH SPEED GROUNDING SWITCH Filed March 9, 1961 4 Sheets-Sheet 5 ll Hbf/W( JM Nov. 10, 1964 K. H. DATE HIGH SPEED GROUNDING SWITCH 4 Sheets-Sheet 4 Filed March 9, 1961 JNVENTOR. /zaa fa/wy Q97:

wx WM rfoR/wsf United States Patent O aisance HGH SPEED GRQUNDING SWITCH Kazuo Henry Date, South Milwaukee, Wis., assigner to McGraw-Edison Company, Milwaukee, Wis., a corporation of Delaware Filed Mar. 9, 196i., Ser. No. Maid@ 12 Claims. (Cl. Zilli-106) This invention relates to electrical switches and, more particularly, to high speed grounding switches.

Grounding switches may be utilized in electrical systems to produce low impedance faults so that a remote circuit interrupter or other backup protective device will be caused to operate. For example, a grounding switch may be utilized on the high side of a transformer bank so that upon the occurrence of a high impedance fault in the transformer, which is insuilcient to operate the backup protective device, the grounding switch closes at high speed to provide a low impedance fault. This insures tast circuit breaker operation before damage to the transformer becomes extensive and eliminates the necessity for expensive high side circuit breakers or fuses.

It is an object of the invention to provide a new and improved high speed grounding switch.

Another obiect of the invention is to provide an inexpensive and compact grounding switch which is reliable during icing conditions.

Another object of the invention is to provide a grounding switch which may be electrically closed and manually reopened by a trip-free operating mechanism which allows the contacts to be closed electrically during a manual resetting operation.

Another object of the invention is to provide a high speed grounding switch having means for indicating the contact position independently of the operating handle.

A still further object of the invention is to provide a high speed grounding switch in which the movable contact is independent of the operating handle and the reset assembly so that inertia during a switch closing operation is minimized to ellect rapid operation.

These and other objects and advantages of the invention will become more apparent from the detailed description of the invention taken with the accompanying drawings in which:

FIG. l is an elevational view, partly in section, of a high speed grounding switch embodying the instant invention;

FlG. 2 is a partial sectional view showing the operating mechanism of the high speed grounding switch of FIG. l wherein the grounding contacts are in open position;

FlG. 3 is a view taken along lines 3--3 of FG. 2;

FIG. 4 is a View of the operating mechanism when the grounding contacts are in closed position;

FIG. 5 is a view illustrating the operation of a portion of the device; and

FIG. 6 is a schematic diagram of the electrical circuit of the grounding switch ccording to the instant invention.

In general terms, the invention includes tixed and movable contact means, switch closing means urging said movable contact toward its closed position, latch means for holding said movable contact in open position, electro-responsive latch release means for freeing said movable contact for movement toward its closed position, manually operable means for resetting said movable Contact in its latched position, said electro-responsive and manual means being independently operable so that said movable contact may be released for movement to its open position during a manual resetting operation.

The invention also includes indicating means connected to the movable contacts and independent of the operating handle so that the contact position will be indicated regardless of the operating handles position.

Refeiring to the drawings in greater detail, in FIG. l the high speed grounding switch according to the instant invention is shown to include a hollow insulator 10 of any suitable material such as porcelain and mounted atop a metallic housing 12 which encloses the devices operating mechanism. Insulator lt) is supported on a metallic base plate 14 ailixed to the upper end of housing l2 and having an upstanding llange 16 which deiines a socket for surrounding the lower end of insulator lt) and for receiving cement 18. A metallic housing 2t) is similarly provided with a depending annular flange 22 for surrounding the upper end of insulator 10 so that it may be cemented thereto at Z3 to provide a fluid-tight joint. The operating mechanism Within housing l2 will be described in detail below, it being suliicient here to state that it is operative to move contact rod 24 in straight line motion through an aperture 25 in base plate 14 and into and out of engagement with the stationary contact assembly 26.

The interior cylindrical bore 28 of insulator it) constitutes a iiuid reservoir lled with dielectric uid such as oil to a level indicated by broken lines 29. The upper metallic housing 2lb includes a cup-shaped body portion 39 and a cover 32 which is suitably aihxed to body portion Sil. An annular gasket 34 disposed between the upper rim of body portion 3l) and cover 32 seals the interior of housing 2t?. An aperture 35 in the center of body portion 30 permits the expansion of the dielectric iiuid into housing 2li and provides an air cushion above said fluid to absorb the iluid displaced as contact rod 24 moves toward its closed position. A packing gland 36 in aperture 25 seals the housing 12 from the oil in insulator 1).

The stationary contact assembly 26 is suspended from metallic housing 2li by a plurality of conductive studs 37 and includes a plurality of segmented contact portions 38 which are slidably mounted between a pair of conductive support plates 39 and 4l). A garter spring l2 which surrounds contact segments 35 provides Contact pressure with rod 2d while a helically wound, annular, conductive, current interchange spring 44 disposed in cooperating grooves do formed in the upper surface of each or the segments 33, which cooperatively engage to form an annular recess, provides current interchange between segments 3B and the upper plate 39. Contact jaw 26 is discussed in further detail in copending application Serial No. 860,821, led December 21, 1959, now Patent Number 3,070,770, and assigned to the assignee of the instant invention.

Current is transferred from contact rod 24 to metallic housing l2 by a stationary wiping contact 48 mounted to the upper end of a tubular conductive member Slt which is disposed concentrically around the contact rod 24 and aiiixed to a metallic support 51 which in turn is rigidly secured to the upper surface of base plate 14. The current path through the grounding switch, when the contact rod 24 is in closed position, is from an adapter 52 aiiixed to cover 32 of housing 2li, through the cover and base portions of housing 20, conductive studs 37, plates 39 and di), contact segments 38, contact rod 24, wiping contacts 48, tubular member 50, base 5l, support plate i4, conductor 55, and adapter 56 to the ground wire (not shown).

The operating mechanism is supported in housing 12 by a mounting plate 58 aihxed to base plate 14 and includes a latching and reset assembly 60 suspended below base plate 53 by mounting plates 6l and 62 which are aiiixed at their upper ends to the base plate 5S and which extend downwardly therefrom. The latching and reset assembly 6l) is connected to contact rod 24 by a straight line linkage 63 and is operable to move contact rod 24 to its open position and to maintain it in said position against the inlluence of closing spring 64. Manual opera- .iaeseo tion of lthe switch is eiiected by an operating handle 69 on the exterior of housing l2 and which is affixed to an operating shaft eti extending through the side of said bOdS.- ing and pivotally mounted on plates 6l,

The straight line linkage includes a pair of parallel latching links 66 which are pivotally mounted at one end about the operating shaft 68 and which are pivotally connected at their other ends to .a point intermediate the ends of a pair of parallel coupling links '70 by a pivot pm 72. One end of coupling links 7d are connected to the lower end of contact rod 24 by a pin '73 while their other ends are pivotally connected at '74 to the lower ends ot a pair of rocker arms 76 whose upper ends are pivotally connected at 7,3 to a bracket member 79 suspended below mounting plate S. Closing spring 64 extends between mounting plate 58 and a pin Sil aiiixed between coupling links '7d at a point intermediate pivotal connection 72 and '74 so that coupling links 7b are urged toward r0- tation in a clockwise direction and contact rod 24 urged upwardly and toward its closed position.

Contact rod 24 is normally restrained in open position by a latch member 32 which is pivotally mounted on a pin 83 extending between support plates 62 and which is provided with a latch tip S4 that engages a latch bar 36 rigidly aiiixed between latch links 66. This prevents rotation of latch link 66 in a counterclockwise direction as viewed in FIG. 2 so that contact rod 24 is prevented from moving toward its closed position. A spring S7 connected at its opposite ends to the lower end of latch link 82 and mounting plate 6l, urges pivotal movement of latch link 82 in a clockwise direction about pin d3 and into latching engagement with latch bar 36. A pair of parallel release levers 88 are iixed to latch arm S2 `by a sleeve 91 which surrounds pin 83 to provide a rigid connection so that latch arm 82 and release lever 8S will pivot in unison around pin 83. A release bar S9 is cai'- ried at `one side of release levers 83 by transversely extending arms 9i?.

A pair of parallel reset plates 93 are pivotally mounted around operating shaft 68 and have a pin 96 extending between their upper ends upon which a pair of reset arms 94 are pivotally mounted. Reset arms 94 are interconnected by a pin 95 while their slotted lower ends 97 are urged toward engagement with latch bar 86 by torsion springs 98 which surround pin 96. In addition, a pair of springs lltlil extending between pin 96 and mounting plates 6l urge rotation of reset plates 93 in a counterclockwise direction but this is prevented by a stop rod lill which is aiiixed between the lower ends of reset plates 93 and engages the undersides of latch links 66.

A driving member MP2 is aiiixed to operating shaft 68 and is urged toward engagement with a driving pin ldd extending between reset plates 93 by a pair of springs 1104 connected at their Vopposite ends to a pin 106 projecting transversely through driving member m2 and pin 96 carried by the upper ends of reset plates 93. Pivotally connected at 108 to the lower end of driving member 102 is a pair of trip links ld@ whose slotted ends are urged by a spring lilll into engagement with' a pin llllZ carried between the lower ends of release arm 3S.

MElbe operating mechanism also includes a trip solenoid i mounted beneath plate 58 and connected to the upper end of release lever e8 by a slotted link lla. triglllllien 1t is desired to close. the grounding switch elec- Iy, solenoid lll4 is energized whereupon slotted link llo is moved toward the left as viewed in FIG. 2 so that 11elease'lever S8 and latch arm 82 are pivoted in a counterclockwise direction about pin S3. This moves latch tip $4 out of engagement with latch bar 86 and also moves release bar S9 into engagement with the reset arms 94 to pivot them in a clockwise direction Vabout pin 9o and Vagainst the influence of Itorsion springs 98. Upon this event, latch link 66 is released for pivotal movement in a counterclockwise direction about operating shaft 63 thereby allowing the closing spring 64 to pivot the coupling link 7@ in a clockwise direction and to move the contact rod 24 upwardly and toward its closed position shown in FlG. 4.

The action of rocker arm 7d during the closing operation provides straight line movement of contact rod This is illustrated in PEG. 4 which shows that as latch link 66 pivots from its open position to an approximately horizontal position shown by the phantom lines, coupling link 'iii forces rocker arm '7e to pivot in a counterclockwise direction about connection '755 to its phantom position. Further movement of Contact rod 24 to closed position, returns rocker arm 76 to its initial position shown by full lines. in this manner, a straight line movement of Contact rod 24 is obtained as it moves from its open position shown in FIG. 2 to its closed position shown by the full lines in FIG. 4.

The pivotal movement of latch links :56 moves their lower ends out of engagement with stop pin lill whereby reset members 93 are released for pivotal movement under the iniiuence of springs ltitl about operating shaft (iii and from their position shown in FlG. 2 to their open position shown in FIG. 4. During this pivotal movement of reset members @3, driving pin ll engages the driving member MP2 forcing it to pivot in a counterclockwise direction .thereby rotating the operating shaft 63. This moves the operating handle 69 from its full position in HG. l to its position shown by broken lines.

The movement of contact rod 24 to its closed position de-energizes solenoid lll/l in a manner to be described hereinafter, so lthat release arm 3S and latch arm S2 are freed for movement to their initial positions under the influence of spring t. This places them in a position to relatch the mechanism when the contact rod 24 is returned to its open position.

It will be appreciated that upon the tripping of con tact rod 24 and straight line linkage 63, they will be free to move to their closed position free of the operating mechanism 6d. As a result the inertia inherent in the mechanism 60 does not affect the closing time of contact rod 24 so that substantially faster closing is possible.

When it is desired to reopen the switch, `operating handle 69 is moved from its phantom position in PEG. l to its full position whereby operating shaft 68 is rotated in a clockwise direction as viewed in PEG. 4. This moves driving member liti?) into engagement with driving pin ldd to force reset members 93 to pivot in a clockwise direction against spring lltld. As reset members 93 pivot, the slotted end 97 of reset arms 94 engage latch bar Se, forcing latch link 65 to pivot in a clockwise direc-l tion .thereby moving Contact rod 24 toward its open position. Such pivotal movement will continue until the fggnd 0f f'flVlg member 1 @2 engages a fixed stop ,i extending between vertical mounting plates lf'laetclhalilr tde will then have moved into engagement with t ip o4 ol latch arm 32 whereby the movable Contact rod 24 is latched in open position.

Tilipfree operation of the switch is provided in the tnat solenoid illd receives a switch closing signal g a manual opening operation or while the operating handle is being held in open position by ice or the like. Upon such an event 'the slotted link le will be moved to the left as viewed in FlG. 2 88 and latch arm 32. in a counterciockwise direction about shaft 33. This will move latch tip S4 out of engagement with latch bar 36 and also the slotted ends 97 of reset arms 94 out of engagement with the latch bar 8:5 so that latch bar $6 is free for pivotal movement in a counterclockwise direction even though reset members 93 continue to be pivoted in a clockwise irection by driving member Hence it can be seen that Contact rod 24 may be electrically released for movement to its closed to rotate release arms position even though the operating handle and the reset mechanism are executing a resetting operation.

Manual tripping of the device is accomplished by moving the operating handle from its open to its closed position whereby operating shaft 68 is rotated in a counterclockwise direction. This moves the lower end of driving member 102 toward the right as viewed in FIG. 2 and against the restraining force of spring 164 to bring the slotted end 110 of trip link 16% into engagement with a pin 112 carried between the lower ends of release arm S8. This pivots the latch tip 34 of latch arm 82 out of engagement with latch bar Se and also moves release bar S9 into engagement with reset arms 94. The release of contact rod 24 then proceeds in the manner described with respect to electrical operation. Trip link 109 is slotted at 111i in order to allow suflicient pivotal movement of driving member 1&2 prior 'to the release of latch link 66 so Ithat said link will not rapidly engage driving pin 1G15 and thereby jerk the operating handle.

In order to give a positive indication oi the position of contact rod 24 without regard to operating handle 59, a 'target 122 is provided on the end of an arm 123 which is amxed to a sleeve 124 that rotatably surrounds operating shaft 68 and which is coupled to the latch links de by an arm 126 and slotted link 127. In addition, sleet shield 1215 which covers operating handle 69 and target link 123 is provided with indicia 128 of Contact position and windows 129 so that the position of the target can readily be seen.

As shown in FIG. 5, arm 126 is atxed at one end to sleeve 124 and carries a pin 13%v at its other end for engaging the slot 132 in link 127. rThe upper end ot link 127 is pivotally connected to latch bar 86 and a spring 134, extending between said latch bar and pin 13d, urges the latter toward the upper end of slot 132. When the latch links 66 move from their open position shown by full lines to their closed position shown by phantom lines, upon the release of latch bar 36, slotted link 127 will be pulled in a counterclockwise direction by spring 134 thereby pivoting target arm 123 from its open to its closed indicating position shown by broken lines in FIG. 1. Should target arm 123 be frozen or otherwise held in its open position thereby preventing such pivotal movement of arm 12e and sleeve 124, slot 132 permits latch links to pivot freely. Because target 122 is coupled to latch link 65 and is independent of operating handle 69, it will indicate the position of contact rod 24 regardless of the position of operating handle 69. In the event, therefore, that contact rod 24 is closed electrically during a manual opening operation, the true position of contact rod 24 will be indicated by target 122.

In order to de-energize solenoid 114 after the grounding switch has been closed, a cam-operated switch 13d, shown in FIGS. 3 and 5, is connected to the latch links 66 and is operable to open circuit solenoid 114 as contact rod 24 moves toward its closed position and to reclose upon movement of contact rod 24 to its open position. For .this purpose a link 13S is pivotally connected at one end -to latch bar 36 and at its other end to the operating arm 139 of switch 13o so that movement of the latch links 66 from their full to their phantom positions in FIG. 5 pivots operating arm 139 in a counterclockwise direction to open switch 13d. Similarly the resetting of latch links 66 in their open position recloses switch 136 as shown by full lines in FIG. 5.

FIG. 6 shows the operation of the grounding switch in relation to the circuit 14d being protected. I-Iere, a fault responsive relay 141 is coupled to line 14th and is operative upon the occurrence of an overcurrent to place solenoid 114 in circuit with an energy source 142. This trips latch 82 in the manner described above to release latch link 66 and contact rod 24 for movement to their closed position which grounds system 141i through stationary contact 25, contact rod 24 and brush contacts 54. In addition, as latch links ed pivot, switch 136 is opened to disconnect solenoid 114 from source 142. The ground fault resulting from the closure of contact rod 24 causes a backup protective device (not shown) to operate and thereby interrupt the system 149.

While only a single embodiment of the invention is shown and described other modifications thereof will become apparent to those skilled in the art. Accordingly, it is intended to cover in the appended claims all such modications that fall within the scope of the invention.

I claim:

l. A high speed grounding switch comprising, xed and movable contact means, switch closing means urging said movable contact means toward its closed position, latch means for holding said movable Contact in open position, electro-responsive latch release means for freeing said movable contact for movement 'toward its closed position, resetting means normally operable to move said movable contact out of its closed position and into its latched position, said electro-responsive latch release means also being operable to render said resetting means ineiective to move said movable contact so that movement of said movable contact out oi' its closed position may be prevented and said movable contact may be released for movement into its closed position it a resetting operation has commenced or when said resetting means is heid in its open position.

2. Switch means comprising fixed and movable contact means, switch closing means urging said movable contact means toward its closed position, latch means for holding said movable contact means in open position, electro-responsive latch release means operatively associated with said latch means and operable to move it out of engagement with said movable contact means thereby freeing said contact for high speed movement toward its closed position, resetting means releasably engaging said movable contact means and operable to move it to its latched position, said electro-responsive latch release means also being operative to disengage said resetting means from said movable Contact means so that movement of said movable contact toward its ciosed position may be prevented and said movable contact may be released for movement to its closed position if a resetting operation has commenced or when said resetting means is held in its open position.

3. Switch means comprising fixed and movable contact means, linkage means connected to said movable contact means, switch closing means urging said movable contact toward its closed position, latch means engaging said linkage means and operable to hold said movable contact means in open position, electro-responsive latch release means connected to said latch means for moving the same out of engagement with said linkage means to free said movable contact means for high speed movement toward its closed position, manually operable resetting means releasably engaging said linkage means and operable to move said movable contact to its latched position, said electro-responsive latch release means also being operative to disengage said resetting means from said linkage means so that movement of said movable contact toward its closed position may be prevented and said movable contact may be released for movement to its closed position if a resetting operation has commenced or when said resetting means is held in its open position.

4. Switch means comprising xed and movable contact means, linkage means connected to said movable contact means, switch closing means urging said movable contact toward its closed position, latch means engaging said linkage means and operable to hold said movable contact in open position, electro-magnetic latch release means connected to said latch means for moving the same out of engagement with said linkage means to free said movable contact for movement toward its closed disastro position, manual operating means including resiliently supported resetting arm means biased toward engagement with said linkage means and constructed and arranged upon movement in a first direction to move said movable contact to its latched position, said manual operating means also being operable upon movement in a second direction to release said latch means, said electromagnetic latch release means also being operative to disengage said resetting arm means from said linkage means so that movement of said movable contact toward its closed position may be prevented and so that said movable contact may be released for movement to its closed position it a resetting operation has commenced without interference by said resetting means.

5. A high speed grounding switch comprising, iixed and movable contact means, spring means connected to said movable contact means for urging it toward engagement with said fixed Contact means7 an operating mechanism including latch means resiliently urged into engagement with said movable contact means and operable to hold the same in open position, electromagnetic latch release means connected to said latch means for moving the same out of engagement with said movable contact thereby freeing it for rapid movement toward its closed position under the influence of said spring means, manually operable resetting means movable between iirst and second positions, and having resiliently supported arm means biased toward engagement with said linkage means and operable upon movement of said resetting means to its first position to move said movable contact to its latched position, said electromagnetic latch release means also being operative to disengagc said arm means from said movable contact means so that movement of said movable contact toward its closed position may be prevented and so that said movable contact will be free to close should the electromagnetic means be energized after a manual resetting operation has commenced.

6. A high speed grounding switch comprising, iixed and movable contact means, spring means connected to said movable contact means for urging it toward engagement with said fixed contact means, an operating mechanism including latch means resiliently urged into engagement with said movable contact means and operable to hold the same in open position, electromagnetic latch release means connected to said latch means for moving the same out of engagement with said movable contact thereby freeing it for rapid movement toward its closed position under the inl'luence of said spring means, manually operable tripping and resetting means including a driving member movable between first and second positions, a resetting member resiliently engaged by said driving member and having resiliently supported arm means biased toward engagement with said linkage means and operable to move said movable contact to its latched position upon movement of said driving member to its iirst position, movement of said driving member to its second position being operative to move said latch means out of engagement with said movable contact, said electromagnetic latch release means also being operative to disengage said arm means from said linkage means so that movement of said movable contact toward its closed position may be prevented and so that said movable contact may be released for movement to its closed position after a manual relatching operation has commenced or when said mechanical resetting means is held in its open position.

7. A high speed grounding switch comprising, stationary contact means, a movable contact rod, an insulating housing surrounding said stationary contact means and containing a quantity of dielectric iiuid, an aperture at the lower end of said insulating housing for slidably receiving the upper end of said contact rod, linkage means connected to the lower end of said Contact rod for guiding the same in straight line motion through 8 said aperture, spring means connected to said linkage for urging said Contact rod toward engagement with said stationary contact means, an operating mechanism supported below said insulating housing and including rotatably mounted latch means resiliently urged into engagement with said linkage means and operable to hold said movable contact means in open position, electromagnetic latch release means connected to said latch means for pivoting the same out of engagement with said linkage means to free said contactV rod for rapid movement tow rd its closed position under the influence of said spring means and independent of said operating mechanism, said operating mechanism including manually operable tripping and resetting means having a rotatably mounted driving member and a resetting member l resiiently engaged by said driving member, arm means resiliently mounted on said resetting member and biased toward engagement with said linkage means and operable upon rotation movement of said driving member in a first direction to move said Contact rod to its latched position, said driving member also being movable into engagement with said trip member upon rotation in a second direction to rotate the latter out of engagement with said linkage means, said electromagnetic latch release means being operative to disengage said arm means from said linkage means so that said movable contact may be released for movement to its closed position while said driving member is moving the same toward its open position or when said resetting means is held in its open position.

8. A high speed grounding switch comprising xed and movable Contact means, spring means urging said movable Contact toward its closed position, latch means for holding said movable contact in open position, electro-responsive latch release means connected to said latch means and operable to free said movable contact for movement toward its closed position, manually operable resetting means including an operating handle resiliently engaging said movable Contact means and operable to move it to its latched position upon movement of said operating handle to a first position, said operating handle being movable to a second position upon the release of said movable contact means by said electro-responsive means, said electro-responsive latch release means also being operative to disengage said resetting means from said movable contact means so that it will be free to close should the electro-responsive means be energized during a manual resetting operation, and indicating means resiliently connected to said movable contact and movable therewith between its opened and closed position to indicate the true position thereof independent of the position of said operating handle, the resilient connection between said movable contact means and said indicating means allowing said movable contact to move to its closed position without interference from said indicating means should the latter be held in its open position.

9. Switch means comprising xed and movable contact means, linkage means connected to said movable Contact means, switch closing means urging said movable contact toward its closed position, latch means engaging said linkage means and operable to hold said movable contact in open position, electro-responsive latch release means connected to said latch means for moving the same out of engagement with said linkage means to free said movable contact for movement toward its closed position, manually operable resetting ymeans including an operating handle resiliently coupled to said linkage means and operable to move said movable contact to its latched position upon movement of said operating handle to a iirst position, said resetting means also being operative to release said latch means upon movement of said operating handle to a second position, said electro-responsive latch release means being operative to disengage said resetting means from 3,1 9 said linkage means so that said movable contact may be released for movement to its closed position while said resetting means is moving the same toward its open position or when said mechanical resetting means is held in its open position, and indicating means resiliently connected to said linkage means and movable therewith as said movable contact travels between its opened and closed position to indicate the true position thereof independent of the position of said operating handle, the resilient connection between said linkage kmeans and said indicating means allowing said movable contact to move to its closed position without interference from said indicating means should the latter be held in its open position.

l0. A high speed grounding switch comprising stationary Contact means, movable contact rod means, spring means biasing said Contact rod toward engagement with said stationary contact means, an operating mechanism including rotatably mounted latch means resiliently urged into engagement with said Contact rod means for holding the same out of engagement with said stationary contact means, electromagnetic latch release means operatively associated with said latch means for rotating the same out of latching engagement with said contact rod means, said operating mechanism including manually operable tripping and resetting means having a rotatably mounted driving member and a resetting member resiliently engaged by said driving member, arm means resiliently mounted on said resetting member and biased toward engagement with said contact rod means and normally operable upon movement of said driving mem-ber in a rst direction to move said contact rod means to its latched position, said driving member also being movable into engagement with said latch means upon rotation in a second direction to rotate the latter out of engagement with said contact rod means, said electromagnetic latch release means also being operative to disengage said arm means from said contact rod means so that movement of said contact rod means toward its open position may be prevented and so that said movable contact rod means may be released for movement to its closed position if a switch opening operation has commenced or when said resetting means is held in its open position.

l1. A high speed grounding switch comprising, stationary contact means, a movable contact rod, an insulating housing surrounding said stationary contact means and containing a quantity of dielectric lluid, an -aperture at the lower end of said insulating housing for slidingly receiving the upper end of said contact rod, linkage means connected to the lower end of said contact rod for guiding the same in a straight line motion through said aperture, spring means resiliently urging said movable contact rod toward engagement with said stationary contact means, latch means engaging said linkage means for holding said contact rod in said open position, electroresponsive latch relase means operatively associated with said latch means and operable to move it out of engageient with said linkage means to thereby free said contact rod for high speed movement toward its closed position, resetting means releasably engaging said linkage and normally operable to move said contact rod to its latched position, said electroresponsive latch release means being operative to disengage said resetting means from said movable Contact rod so that movement of said movable contact toward its open position may be prevented and so that said movable Contact may be released for movement to its closed position if a resetting operation has commenced or when said resetting means is held in its open position.

12. Switch means comprising xed and movable contact means, switch closing means urging said movable contact means toward its closed position, latch means for holding said movable contact means in open position, electroresponsive latch release means operatively associated with said latch means and operable to release said movable contact means for high speed movement toward its closed position, manually operable resetting means including an operating handle releasably coupled to said movable contact means, movement of said operating handle to a rst position being normally operative to move said movable contact means into its latched position, said operating handle being movable to a second position upon the release of said movable Contact means by said electroresponsive means, said electroresponsive latch release means also being operative to disengage said operating handle from said movable contact means so that the latter will be free to close should the latch release means be energized during the manual resetting operation, and indicating means resiliently coupled to said movable contact means and operable therewith between its open and closed positions to indicate the true position thereof independent of the position of said operating handle, the resilient connection between said movable Contact means and said indicating means allowing said movable contact to move to its closed position without interference from said indicating means should the latter be held in its open position.

`References Cited in the tile of this patent UNlTED STATES PATENTS 2,448,695 Van Ryan Sept. 7, 1948 2,748,221 Edwards et al May 29, 1956 2,816,191 Epstein Dec. l0, 1957 2,860,207 Rigert Nov. l1, 1958 2,874,247 Platz et al. Feb. 17, 1959 2,892,127 Leonard lune 23, 1959 2,994,753 Astelford et al. Aug. l, 1961 

1. A HIGH SPEED GROUNDING SWITCH COMPRISING, FIXED AND MOVABLE CONTACT MEANS, SWITCH CLOSING MEANS URGING SAID MOVABLE CONTACT MEANS TOWARD ITS CLOSED POSITION, LATCH MEANS FOR HOLDING SAID MOVABLE CONTACT IN OPEN POSITION, ELECTRO-RESPONSIVE LATCH RELEASE MEANS FOR FREEING SAID MOVABLE CONTACT FOR MOVEMENT TOWARD ITS CLOSED POSITION, RESETTING MEANS NORMALLY OPERABLE TO MOVE SAID MOVABLE CONTACT OUT OF ITS CLOSED POSITION AND INTO ITS LATCHED POSITION, SAID ELECTRO-RESPONSIVE LATCH RELEASE MEANS ALSO BEING OPERABLE TO RENDER SAID RESETTING MEANS 